Tocotrienol-rich rice “Oonari” as a replacement for corn in the diets of finishing pigs: Effect on pork quality and shelf life

In this study, we firstly verified that a new variety of forage rice “Oonari” as vitamin E-rich grain, especially in γ-tocotrienol than edible “Standard” rice. Our objective was to determine the effects of feeding “Oonari” (T3 rice) on meat quality parameters and shelf life. A total of 45 crossbred finishing pigs were fed either 20% or 45% T3 brown rice containing experimental diets as a replacement for corn (Rice 20 and Rice 45, respectively), and they were compared with 16 crossbred pigs finished with corn-based commercial diet (Basic). After more than 2 months of feeding period, pigs were slaughtered. The longissimus muscle was removed from the loin on day 4 after slaughter, and sliced pork chops (4×4×2 cm) wrapped in polyvinyl chloride film were retail displayed at 4℃ under a LED light for up to 6 days. During storage, values of lightness (L*) and yellowness (b*) decreased, while the levels of redness (a*), drip loss, and thiobarbituric acid reactive substances (TBARS) increased. Chops from T3 rice-fed pigs lessened the amount of drip loss and TBARS than chops from Basic-fed pigs. The lower shear force value was observed in T3 rice-fed samples than Basic-fed samples, but cook loss was not affected by the type of diet. When compared to Basic-fed pigs’ muscle, either sides of the longissimus muscles from shoulder and lumber of T3 rice-fed pigs showed low protein and high fat contents. We also found that feeding T3 rice decreased fatty acid composition of C18 : 2 in all three tissues ; longissimus muscle, subcutaneous fat and intermuscular fat. There was no clear difference in pork quality between Rice 20 and Rice 45 treatment. Overall, these results indicated that feeding T3 rice as a replacement of corn in diets for finishing pigs may have positive effects on pork quality, thus leads to an improvement in the shelf life of chilled raw pork.